A slightly greater DOF bringing the front of the links into focus would have been nice. But if I had to have such a shallow DOF, I would have put it right where ou did. I like this shot.
Overall, I find the subject a bit bland and the central black area takes away from the sharper points at the top and bottom. It's a nicely composed photo.
strange how it seem to be in focus on top and bottom but not in middle. ok, I understand now, the plan of focus is behind the front of the closest link. Deeper DOF is my recommendation.